Automatic air rifle

ABSTRACT

A receiver of an automatic air rifle includes a front sliding sleeve including upper and lower recesses; a main biasing member secured to the front sliding sleeve and the charging handle respectively; a roller; an L-shaped rod; a rear diversion channel through the front sliding sleeve; a rear sliding sleeve including pivotal upper and lower hooks; a main tube through the rear sliding sleeve and including a rear inlet and an annular flange proximate the rear inlet; a gas piston disposed forwardly of the main tube; an inlet member at a rear end of the gas piston; and an auxiliary biasing member put on the main tube and biased between the front sliding sleeve and the rear sliding sleeve. The air rifle is capable of firing in semi-automatic or fully automatic position.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention relates to air rifles and more particularly to a feedingmechanism of an automatic air rifle having improved characteristics.

2. Description of Related Art

A conventional automatic firearm capable of automatic or semiautomaticfire is comprised of a receiver having a moveable hammer locatedtherein; a selector rotatably mounted in the receiver, a first searrotatably mounted in the receiver to engage the hammer, the first searcontacting a first camming surface of the selector; a second searrotatably mounted in the receiver to engage the hammer, the second searcontacting a second camming surface of the selector; and a disconnectrotatably mounted in the receiver, the disconnect contacting a thirdcamming surface of the selector. The selector has a number of selectablepositions so that rotation of the selector between a first position anda last position of the selectable positions is less than 180 degrees.

While the device enjoys its success in the market, continuingimprovements in the exploitation of feeding mechanism of an air gun ofrifle type are constantly sought.

SUMMARY OF THE INVENTION

It is therefore one object of the invention to provide an automatic airrifle capable of automatic and semiautomatic fire comprising a receiver;a hollow limit member secured to a rear portion of the receiver; aspring-actuated cup member disposed in the limit member; an elongatedcavity disposed in the receiver; a receptacle disposed at a front end ofthe cavity; an air chamber disposed at a rear end of the cavity; a firecontrol selector rotatably mounted on the receiver, the fire controlselector being configured to rotate to point to a safe position, asemi-automatic position, or a fully automatic position; a cam memberdisposed in the receiver and co-rotated with the fire control selector;a first spring-biased member disposed to the left of the cam member; asecond spring-biased member disposed to the right of the cam member; aspring-biased trigger pivotably secured to the receiver; a spring-biasedpivotal member partially disposed in the trigger; a charging handleretractably disposed in the receiver; a front sliding sleeve disposed ina forward portion of the cavity and including an upper recess at a rearend and a lower recess under the upper recess; a main biasing memberspaced from the front sliding sleeve, the main biasing member secured tothe receiver and the charging handle respectively; a roller rotatablydisposed in the cavity; an L-shaped rod disposed in the cavity; a rearstop member disposed at an end of a short part of the L-shaped rod andbetween the cam member and the second spring-biased member; a front stopmember disposed at an end of a long part of the L-shaped rod; a reardiversion channel formed through the front sliding sleeve; a rearsliding sleeve disposed rearward of the front sliding sleeve andincluding a spring-biased, pivotal upper hook and a spring-biased,pivotal lower hook; a main tube disposed through the rear sliding sleeveand having a rear end slidably disposed in the cup member, and a frontend fastened in the front sliding sleeve, the main tube including a rearinlet and an annular flange disposed forwardly of the rear inlet; a gaspiston disposed forwardly of the main tube and forwardly of the frontsliding sleeve, the gas piston having a front end disposed in thereceptacle; a magazine releasably secured to the receiver and includinga column for storing at least one pellet wherein one of the at least onepellet is pushed to contact an outer surface of the front end of the gaspiston; a barrel having a rear end communicating with the front end ofthe gas piston; an inlet member formed at a rear end of the gas piston;and an auxiliary biasing member put on the main tube and biased betweenthe front sliding sleeve and the rear sliding sleeve; wherein inresponse to rotating the fire control selector to the semi-automaticposition, the cam member is disposed perpendicular to both the first andsecond spring-biased members, the rear stop member is not urged by thecam member, a pulling of the charging handle pulls the front slidingsleeve to be proximate the main tube, the gas piston moves rearward toallow one of the at least one pellet to enter the receptacle, the mainbiasing member expands, the upper hook lockingly engages the upperrecess, the lower hook lockingly engages the lower recess, the auxiliarybiasing member compresses, a releasing of the charging handle compressesthe main biasing member to push both the front and rear sliding sleevesforward, the gas piston moves forward to push one of the at least onepellet into a rear end of the barrel, the upper hook is pressed by theroller in the forward movement of the rear sliding sleeve to disengagefrom the upper recess, a pulling of the trigger counterclockwise rotatesboth the pivotal member and the lower hook to unlock the front slidingsleeve, the auxiliary biasing member expands to push the rear slidingsleeve rearward, the main tube moves rearward to compress the cup memberuntil the flange contacts the limit member and the rear inletcommunicates with the air chamber, pressurized gas flows through thebarrel via the air chamber, the rear inlet, the main tube, and the gaspiston to discharge one of the at least one pellet out of the barrel, aportion of the pressurized gas flows into the diversion channel to pushthe front sliding sleeve rearward by compressing the auxiliary biasingmember and expanding the main biasing member, the gas piston movesrearward to allow a next one of the at least one pellet to enter thereceptacle, a stop of flowing the pressurized gas pushes the cup memberforward to disengage the rear inlet from the air chamber, the upper hooklockingly engages the upper recess, the lower hook lockingly engages thelower recess, a pulling of the trigger counterclockwise rotates thepivotal member and moves the pivotal member along an outer surface ofthe lower hook without counterclockwise rotating the lower hook, themain biasing member compresses to push the rear sliding sleeve forwardand compress the auxiliary biasing member, the upper hook is pressed bythe roller in the forward movement of the rear sliding sleeve todisengage from the upper recess, and a release of the trigger clockwiserotates the pivotal member to disengage from the lower hook to disposethe trigger in a ready position; and wherein in response to rotating thefire control selector to the fully automatic position, the cam member isdisposed perpendicular to both the first and second spring-biasedmembers, the rear stop member is not urged by the cam member, a pullingof the charging handle pulls the front sliding sleeve to be proximatethe main tube, the gas piston moves rearward to allow one of the atleast one pellet to enter the receptacle, the main biasing memberexpands, the upper hook lockingly engages the upper recess, the lowerhook lockingly engages the lower recess, the auxiliary biasing membercompresses, a releasing of the charging handle compresses the mainbiasing member to push both the front and rear sliding sleeves forward,the gas piston moves forward to push one of the at least one pellet intoa rear end of the barrel, the upper hook is pressed by the roller in theforward movement of the rear sliding sleeve to disengage from the upperrecess, a pulling of the trigger counterclockwise rotates both thepivotal member and the lower hook to unlock the front sliding sleeve,the auxiliary biasing member expands to push the rear sliding sleeverearward, the main tube moves rearward to compress the cup member untilthe flange contacts the limit member and the rear inlet communicateswith the air chamber, first pressurized gas flows through the barrel viathe air chamber, the rear inlet, the main tube, and the gas piston todischarge one of the at least one pellet out of the barrel, a portion ofthe first pressurized gas flows into the diversion channel to push thefront sliding sleeve rearward by compressing the auxiliary biasingmember and expanding the main biasing member, the gas piston movesrearward to allow a next one of the at least one pellet to enter thereceptacle, a stop of flowing the first pressurized gas pushes the cupmember forward to disengage the rear inlet from the air chamber, theupper hook lockingly engages the upper recess, the lower hook lockinglyengages the lower recess, the main biasing member compresses, theauxiliary biasing member compresses to push the rear sliding sleeveforward, the upper hook is pressed by the roller in the forward movementof the rear sliding sleeve to disengage from the upper recess, a pullingof the trigger counterclockwise rotates both the pivotal member and thelower hook to unlock the front sliding sleeve, the auxiliary biasingmember expands to push the rear sliding sleeve forward, the upper hookis pressed by the roller in the forward movement of the rear slidingsleeve to disengage from the upper recess, the pivotal member pivotablypushes the lower hook to disengage from the lower recess, the auxiliarybiasing member expands to push the rear sliding sleeve rearward, themain tube moves rearward to compress the cup member until the flangecontacts the limit member and the rear inlet communicates with the airchamber, second pressurized gas flows through the barrel via the airchamber, the rear inlet, the main tube, and the gas piston to dischargeone of the at least one pellet out of the barrel, a portion of thesecond pressurized gas flows into the diversion channel to push thefront sliding sleeve rearward by compressing the auxiliary biasingmember and expanding the main biasing member, the gas piston movesrearward to allow a next one of the at least one pellet to enter thereceptacle, a stop of flowing the second pressurized gas pushes the cupmember forward to disengage the rear inlet from the air chamber, theupper hook lockingly engages the upper recess, the lower hook lockinglyengages the lower recess, the main biasing member, the main biasingmember expands, the auxiliary biasing member compresses, and both thefront and rear sliding sleeves move forward to dispose the trigger in aready position.

The above and other objects, features and advantages of the inventionwill become apparent from the following detailed description taken withthe accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side elevation of an automatic air rifle according to theinvention;

FIG. 1A is a detailed view of the area in a rectangle of FIG. 1;

FIG. 2 is a longitudinal sectional view of the bolt carrier in thereceiver but shown in an acute angle;

FIG. 3 is a longitudinal sectional view of the bolt carrier in thereceiver showing the fire control selector rotated to the semi-automaticposition in a first firing mode;

FIG. 4 is a view similar to FIG. 3 showing the gas piston pushedbackward, the main spring expanded, and a round pushed upward to a readyposition by pulling the charging handle rearward;

FIG. 5 is a view similar to FIG. 4 showing the gas piston pushedforward, the main spring compressed, and the round pushed forward asmall distance by releasing the charging handle;

FIG. 6 is a view similar to FIG. 5 showing the trigger being pulled tostart a firing process;

FIG. 7 is a view similar to FIG. 6 showing the round being fired at theend of pulling the trigger;

FIG. 8 is a view similar to FIG. 7 showing a portion of the gasses beingdiverted to push the front sliding sleeve rearward, and a new roundbeing pushed upward after firing the round;

FIG. 9 is a view similar to FIG. 8 showing the gas piston being pushedbackward and the new round pushed to a ready to fire position;

FIG. 10 is a view similar to FIG. 9 showing the trigger being pulled andactions of other associated components;

FIG. 11 is a view similar to FIG. 10 showing the trigger being releasedand actions of other associated components;

FIG. 12 is a view similar to FIG. 11 showing the trigger and otherassociated components in a ready to fire position;

FIG. 13 is a view similar to FIG. 1A showing the fire control selectorrotated to the automatic position in a second firing mode;

FIG. 14 is a longitudinal sectional view of the bolt carrier in thereceiver showing the fire control selector in the automatic position;

FIG. 15 is a view similar to FIG. 14 showing the gas piston pushedbackward, the main spring expanded, and a round pushed upward to a readyposition by pulling the charging handle rearward;

FIG. 16 is a view similar to FIG. 15 showing the charging handle beingreleased and the front sliding sleeve being moved forward, and the roundbeing ready;

FIG. 17 is a view similar to FIG. 16 showing the gas piston pushedforward, the main spring compressed, and the round pushed forward asmall distance after releasing the charging handle;

FIG. 18 is a view similar to FIG. 17 showing the trigger being pulled tostart a firing process;

FIG. 19 is a view similar to FIG. 18 showing the round being fired atthe end of pulling the trigger;

FIG. 20 is a view similar to FIG. 19 showing a portion of the gassesbeing diverted to push the front sliding sleeve rearward, and a newround being pushed upward after firing the round;

FIG. 21 is a view similar to FIG. 20 showing the gas piston being pushedbackward, and the new round pushed to a ready to fire position;

FIG. 22 is a view similar to FIG. 21 showing the trigger and actions ofother associated components;

FIG. 23 is a view similar to FIG. 22 showing a portion of the gassesbeing about to divert to the push the front sliding sleeve rearward andactions of other associated components after firing;

FIG. 24 is a view similar to FIG. 23 showing the portion of the gassesbeing diverted to the push the front sliding sleeve rearward and actionsof other associated components after firing;

FIG. 25 is a view similar to FIG. 24 showing the front sliding sleevebeing locked by the rear sliding sleeve due to the diversion of thegasses;

FIG. 26 is a view similar to FIG. 25 showing the trigger being returnedto its inoperative position; and

FIG. 27 is a view similar to FIG. 26 showing the front sliding sleeveand the rear sliding sleeve being unlocked after the trigger returningto its inoperative position.

DETAILED DESCRIPTION OF THE INVENTION

Referring to FIGS. 1 to 27, an automatic air rifle in accordance withthe invention comprises the following components as discussed in detailbelow in which a first firing mode of the air rifle is discussed inFIGS. 1 to 12.

A receiver 1 is provided. An elongated internal cavity 11 is provided inthe receiver 1. A receptacle 12 is provided at a front end of the cavity11. An air chamber 13 is provided at a rear end of the cavity 11. A firecontrol selector 14 is rotatably mounted on the receiver 1. The firecontrol selector 14 can be rotated to point to a “SAFE” (i.e., at whichthe air rifle cannot be fired) mode, a “SEMI” (i.e., semi-automatic)mode, or an “AUTO” (i.e., fully automatic) mode. A cam member 15 isprovided in the receiver 1 and co-rotated with the fire control selector14. A first spring-biased member 151 is provided to the left of the cammember 15 and a second spring-biased member 152 is provided to the rightof the cam member 15 respectively (see FIG. 2). An exposed trigger 16 ispivotably secured to the receiver 1. The trigger 16 is pivotal because,at least, a forward spring 17 is provided in a front portion and a rearspring 19 is provided in a rear portion. The rear spring 19 is biasedbetween the trigger 16 and a pivotal member 18 which is rearward of therear spring 19. A charging handle 10 is provided in the receiver 1 andexposed so that a user may pull or push the charging handle 10. A frontsliding sleeve 2 is provided in a forward portion of an intermediateportion of the cavity 11. A main spring 20 is provided above the frontsliding sleeve 2. The main spring 20 has one end fastened in thereceiver 1 and the other end secured to the charging handle 10 which inturn is secured to the front sliding sleeve 2. Thus, the charging handle10 is made a spring-actuated member and the front sliding sleeve 2 isconfigured to move in response to compression or expansion of the frontsliding sleeve 2.

A roller 21 is provided on an upper portion of the cavity 11. AnL-shaped rod 3 is provided on a lower portion of the cavity 11. A rearstop member 31 s provided at an end of the short part of the L-shapedrod 3. The rear stop member 31 is disposed between the cam member 15 andthe second spring-biased member 152 and contacts the same respectively.A front stop member 32 is provided at an end of the long part of theL-shaped rod 3. The front sliding sleeve 2 has a forward part and a rearpart having a diameter less than that of the forward art. A diversionchannel 22 is formed through an intermediate portion of the frontsliding sleeve 2 joining the forward part and the rear part of the frontsliding sleeve 2. A rear sliding sleeve 4 is provided rearward of thefront sliding sleeve 2 and includes a spring-biased, pivotal upper hook41 configured to lockingly engage an upper recess 23 at a rear end ofthe front sliding sleeve 2, and a spring-biased, pivotal lower hook 42configured to lockingly engage a lower recess 24 at the rear end of thefront sliding sleeve 2. A main tube 5 is provided through the rearsliding sleeve 4 and has a rear end fastened in a spring-actuated cupmember 71 at a rear portion of the receiver 1. The cup member 71 isfastened in a hollow limit member 7 which is secured to the rear portionof the receiver 1. A front end of the main tube 5 is fastened in thefront sliding sleeve 2. An inlet 51 is provided proximate the rear endof the main tube 5. An annular flange 52 is provided adjacent to therear end. The flange 52 is between a rear end of the upper hook 41 and arear end of the lower hook 42. A gas piston 54 is provided forwardly ofthe main tube 5. The gas piston 54 has a front end in the receptacle 12and a substantial portion disposed in the front sliding sleeve 2. Apellet 53 stored in a column 61 of a magazine 6 is pushed to contact anouter surface of the front end of the gas piston 54. A barrel 50 has arear end in communication with the front end of the gas piston 54. Aninlet 55 is provided at a rear end of the gas piston 54. An auxiliaryspring 40 is put on the main tube 5 and biased between the front slidingsleeve 2 and the rear sliding sleeve 4. Thus, the front sliding sleeve 2is made into a spring-actuated member.

The first firing mode is discussed be low. In response to rotating thefire control selector 14 to the “SEMI” position (see FIG. 1A), the cammember 15 is disposed upright as shown in FIG. 3. The rear stop member31 is not urged by the cam member 15. Next, a user may pull the charginghandle 10 to pull the front sliding sleeve 2 (i.e., moving rearward) toa position proximate the front end of the main tube 5 (see FIG. 4). Thegas piston 54 moves rearward a short distance to allow the pellet 53 toenter the receptacle 12. And in turn, the main spring 20 expands. Also,the upper hook 41 lockingly engages the upper recess 23 and the lowerhook 42 lockingly engages the lower recess 24. Also, the auxiliaryspring 40 is compressed. This is a ready to fire position. Afterreleasing the charging handle 10, the main spring 20 compresses to pushboth the front sliding sleeve 2 and the rear sliding sleeve 4 forward.And in turn, the gas piston 54 moves forward to push the pellet 53 intoa rear end of the barrel 50 to be ready to fire. The upper hook 41 ispressed by the roller 21 in the forward movement of the rear slidingsleeve 4. Thus, the front end of the upper hook 41 clears the upperrecess 23 (see FIG. 5). The user may pull the trigger 16 tocounterclockwise rotate the pivotal member 18. The counterclockwiserotation of the pivotal member 18 counterclockwise rotates the lowerhook 42, thereby unlocking the front sliding sleeve 2 (see FIG. 6). Theauxiliary spring 40 then expands to push the rear sliding sleeve 4rearward (see FIG. 7). The main tube 5 moves rearward to compress thecup member 71 until the flange 52 contacts the limit member 71, and theinlet 51 communicates with the air chamber 13. Pressurized gas from anair canister (not shown) flows to the air chamber 13 and in turn flowsthrough the main tube 5 via the inlet 51. And in turn, the gas flowsthrough the gas piston 54 to discharge the pellet 53 out of the barrel50 to fire. At the same time, a portion of the gas flows into thediversion channel 22 to push the front sliding sleeve 2 rearward bycompressing the auxiliary spring 40 and expanding the main spring 20(see FIGS. 7, 8 and 9). And in turn, the gas piston 54 moves rearward tounblock the top opening of the column 61, resulting in a new pellet 53being pushed upward into the receptacle 12 to be ready for a nextfiring. Gas is stopped from supplying to the air chamber 13. The cupmember 71 is pushed forward due to the expansion of the elasticcomponent thereof. The flow path from the air chamber 13 to main tube 5via the inlet 51 is blocked due to the disengagement the inlet 51 fromthe air chamber 13. Further, the upper hook 41 lockingly engages theupper recess 23 and the lower hook 42 lockingly engages the lower recess24. This loading of pellet is automatic. Next, as shown in FIGS. 10 and11, the user may pull the trigger 16 to cause the pivotal member 18 tocounterclockwise rotate. The counterclockwise rotation of the pivotalmember 18 compresses the rear spring 19 so that the pivotal member 18may moves along the outer surface of a lower portion of the lower hook42 without counterclockwise rotating the lower hook 42. The main spring20 then compresses to push the rear sliding sleeve 4 forward, therebycompressing the auxiliary spring 40. The upper hook 41 is pressed by theroller 21 in the forward movement of the rear sliding sleeve 4. Thus,the front end of the upper hook 41 clears the upper recess 23. The usermay release the trigger 16 to expand the rear spring 19, therebyclockwise rotating the pivotal member 18 to disengage from the lowerhook 42 to return to the ready position (see FIG. 12).

As shown in FIGS. 13 to 27, a second firing mode of the air rifle isdiscussed below. In response to rotating the fire control selector 14 tothe “AUTO” position (see FIG. 13), the cam member 15 is disposedhorizontal as shown in FIG. 14. The rear stop member 31 moves rearwardto be clamped by and between the cam member 15 and the secondspring-biased member 152. The lower hook 42 is not supported by thepivotal member 18. Next, a user may pull the charging handle 10 to pullthe front sliding sleeve 2 (i.e., moving rearward) to a positionproximate the front end of the main tube 5 (see FIG. 15). The gas piston54 moves rearward a short distance to allow the pellet 53 to enter thereceptacle 12. And in turn, the main spring 20 expands. Also, the upperhook 41 lockingly engages the upper recess 23 and the lower hook 42lockingly engages the lower recess 24. Also, the auxiliary spring 40 iscompressed. This is a ready to fire position. After releasing thecharging handle 10, the main spring 20 compresses to push both the frontsliding sleeve 2 and the rear sliding sleeve 4 forward. And in turn, thegas piston 54 moves forward to push the pellet 53 into a rear end of thebarrel 50 to be ready to fire (FIG. 17). The upper hook 41 is pressed bythe roller 21 in the forward movement of the rear sliding sleeve 4.Thus, the front end of the upper hook 41 clears the upper recess 23. Theuser may pull the trigger 16 to counterclockwise rotate the pivotalmember 18 (see FIG. 18). The counterclockwise rotation of the pivotalmember 18 counterclockwise rotates the lower hook 42, thereby unlockingthe front sliding sleeve 2 (see FIG. 19). The auxiliary spring 40 thenexpands to push the rear sliding sleeve 4 rearward. The main tube 5moves rearward to compress the cup member 71 until the flange 52contacts the limit member 71 and the inlet 51 communicates with the airchamber 13 (see FIG. 20). Pressurized gas from an air canister (notshown) flows to the air chamber 13 and in turn flows through the maintube 5 via the inlet 51. And in turn, the gas flows through the gaspiston 54 to discharge the pellet 53 out of the barrel 50 to fire. Atthe same time, a portion of the gas flows into the diversion channel 22to push the front sliding sleeve 2 rearward by compressing the auxiliaryspring 40 and expanding the main spring 20 (see FIGS. 19, 20 and 21).And in turn, the gas piston 54 moves rearward to unblock the top openingof the column 61, resulting in a new pellet 53 being pushed upward intothe receptacle 12 to be ready for a next firing. Gas is stopped fromsupplying to the air chamber 13. The cup member 71 is pushed forward dueto the expansion of the elastic component thereof. The flow path fromthe air chamber 13 to main tube 5 via the inlet 51 is blocked due to thedisengagement the inlet 51 from the air chamber 13. Further, the upperhook 41 lockingly engages the upper recess 23 and the lower hook 42lockingly engages the lower recess 24. This loading of pellet isautomatic. Next, as shown in FIG. 22, the compression of the main spring20 and the compression of the auxiliary spring 40 pushes the rearsliding sleeve 4 forward. And in turn, the upper hook 41 is pressed bythe roller 21 in the forward movement of the rear sliding sleeve 4,thereby disengaging the front end of the upper hook 41 from the upperrecess 23. Also, the pivotal member 18 pivotably pushes the rear portionof the lower hook 41 upward to disengage the front end of the lower hook42 from the lower recess 24. The auxiliary spring 40 then expands topush the rear sliding sleeve 4 rearward. The main tube 5 moves rearwardto compress the cup member 71 until the flange 52 contacts the limitmember 71 and the inlet 51 communicates with the air chamber 13 (seeFIG. 23). Pressurized gas from an air canister (not shown) flows to theair chamber 13 and in turn flows through the main tube 5 via the inlet51. And in turn, the gas flows through the gas piston 54 to dischargethe pellet 53 out of the barrel 50 to fire. At the same time, a portionof the gas flows into the diversion channel 22 to push the front slidingsleeve 2 rearward by compressing the auxiliary spring 40 and expandingthe main spring 20 (see FIGS. 23, 24 and 25). And in turn, the gaspiston 54 moves rearward to unblock the top opening of the column 61,resulting in a new pellet 53 being pushed upward into the receptacle 12to be ready for a next firing. Gas is stopped from supplying to the airchamber 13. The cup member 71 is pushed forward due to the expansion ofthe elastic component thereof. The flow path from the air chamber 13 tomain tube 5 via the inlet 51 is blocked due to the disengagement theinlet 51 from the air chamber 13. Further, the upper hook 41 lockinglyengages the upper recess 23 and the lower hook 42 lockingly engages thelower recess 24. The main spring 20 is expanded and the auxiliary spring40 is compressed. This loading of pellet is automatic. Next, as shown inFIG. 25, the user may pull the trigger 16 but the pivotal member 18 doesnot pivot. A releasing of the trigger 16 disengages the pivotal member18 from the front stop member 32 due to expansion of the rear spring 19(see FIG. 26). Finally, both the front sliding sleeve 2 and the rearsliding sleeve 4 move forward to a ready to fire position of theautomatic firing mode (see FIG. 27).

While the invention has been described in terms of preferredembodiments, those skilled in the art will recognize that the inventioncan be practiced with modifications within the spirit and scope of theappended claims.

What is claimed is:
 1. An automatic air rifle capable of automatic andsemiautomatic fire comprising: a receiver; a hollow limit member securedto a rear portion of the receiver; a spring-actuated cup member disposedin the limit member; an elongated cavity disposed in the receiver; areceptacle disposed at a front end of the cavity; an air chamberdisposed at a rear end of the cavity; a fire control selector rotatablymounted on the receiver, the fire control selector being configured torotate to point to a safe position, a semi-automatic position, or afully automatic position; a cam member disposed in the receiver andco-rotated with the fire control selector; a first spring-biased memberdisposed to the left of the cam member; a second spring-biased memberdisposed to the right of the cam member; a spring-biased triggerpivotably secured to the receiver; a spring-biased pivotal memberpartially disposed in the trigger; a charging handle retractablydisposed in the receiver; a front sliding sleeve disposed in a forwardportion of the cavity and including an upper recess at a rear end and alower recess under the upper recess; a main biasing member secured tothe front sliding sleeve and the charging handle respectively; a rollerrotatably disposed in the cavity; an L-shaped rod disposed in thecavity; a rear stop member disposed at an end of a short part of theL-shaped rod and between the cam member and the second spring-biasedmember; a front stop member disposed at an end of a long part of theL-shaped rod; a rear diversion channel formed through the front slidingsleeve; a rear sliding sleeve disposed rearward of the front slidingsleeve and including a spring-biased, pivotal upper hook and aspring-biased, pivotal lower hook; a main tube disposed through the rearsliding sleeve and having a rear end slidably disposed in the cupmember, and a front end fastened in the front sliding sleeve, the maintube including a rear inlet and an annular flange disposed forwardly ofthe rear inlet; a gas piston disposed forwardly of the main tube andpartially in the front sliding sleeve, the gas piston having a front enddisposed in the receptacle; a magazine releasably secured to thereceiver and including a column for storing at least one pellet whereinone of the at least one pellet is pushed to contact an outer surface ofthe front end of the gas piston; a barrel having a rear endcommunicating with the front end of the gas piston; an inlet memberformed at a rear end of the gas piston; and an auxiliary biasing memberput on the main tube and biased between the front sliding sleeve and therear sliding sleeve; wherein in response to rotating the fire controlselector to the semi-automatic position, the cam member is disposedperpendicular to both the first and second spring-biased members, therear stop member is not urged by the cam member, a pulling of thecharging handle pulls the front sliding sleeve to be proximate the maintube, the gas piston moves rearward to allow one of the at least onepellet to enter the receptacle, the main biasing member expands, theupper hook lockingly engages the upper recess, the lower hook lockinglyengages the lower recess, the auxiliary biasing member compresses, areleasing of the charging handle compresses the main biasing member topush both the front and rear sliding sleeves forward, the gas pistonmoves forward to push one of the at least one pellet into a rear end ofthe barrel, the upper hook is pressed by the roller in the forwardmovement of the rear sliding sleeve to disengage from the upper recess,a pulling of the trigger counterclockwise rotates both the pivotalmember and the lower hook to unlock the front sliding sleeve, theauxiliary biasing member expands to push the rear sliding sleeverearward, the main tube moves rearward to compress the cup member untilthe flange contacts the limit member and the rear inlet communicateswith the air chamber, pressurized gas flows through the barrel via theair chamber, the rear inlet, the main tube, and the gas piston todischarge one of the at least one pellet out of the barrel, a portion ofthe pressurized gas flows into the diversion channel to push the frontsliding sleeve rearward by compressing the auxiliary biasing member andexpanding the main biasing member, the gas piston moves rearward toallow a next one of the at least one pellet to enter the receptacle, astop of flowing the pressurized gas pushes the cup member forward todisengage the rear inlet from the air chamber, the upper hook lockinglyengages the upper recess, the lower hook lockingly engages the lowerrecess, a pulling of the trigger counterclockwise rotates the pivotalmember and moves the pivotal member along an outer surface of the lowerhook without counterclockwise rotating the lower hook, the main biasingmember compresses to push the rear sliding sleeve forward and compressthe auxiliary biasing member, the upper hook is pressed by the roller inthe forward movement of the rear sliding sleeve to disengage from theupper recess, and a release of the trigger clockwise rotates the pivotalmember to disengage from the lower hook to dispose the trigger in aready position; and wherein in response to rotating the fire controlselector to the fully automatic position, the cam member is disposedperpendicular to both the first and second spring-biased members, therear stop member is not urged by the cam member, a pulling of thecharging handle pulls the front sliding sleeve to be proximate the maintube, the gas piston moves rearward to allow one of the at least onepellet to enter the receptacle, the main biasing member expands, theupper hook lockingly engages the upper recess, the lower hook lockinglyengages the lower recess, the auxiliary biasing member compresses, areleasing of the charging handle compresses the main biasing member topush both the front and rear sliding sleeves forward, the gas pistonmoves forward to push one of the at least one pellet into a rear end ofthe barrel, the upper hook is pressed by the roller in the forwardmovement of the rear sliding sleeve to disengage from the upper recess,a pulling of the trigger counterclockwise rotates both the pivotalmember and the lower hook to unlock the front sliding sleeve, theauxiliary biasing member expands to push the rear sliding sleeverearward, the main tube moves rearward to compress the cup member untilthe flange contacts the limit member and the rear inlet communicateswith the air chamber, first pressurized gas flows through the barrel viathe air chamber, the rear inlet, the main tube, and the gas piston todischarge one of the at least one pellet out of the barrel, a portion ofthe first pressurized gas flows into the diversion channel to push thefront sliding sleeve rearward by compressing the auxiliary biasingmember and expanding the main biasing member, the gas piston movesrearward to allow a next one of the at least one pellet to enter thereceptacle, a stop of flowing the first pressurized gas pushes the cupmember forward to disengage the rear inlet from the air chamber, theupper hook lockingly engages the upper recess, the lower hook lockinglyengages the lower recess, the main biasing member compresses, theauxiliary biasing member compresses to push the rear sliding sleeveforward, the upper hook is pressed by the roller in the forward movementof the rear sliding sleeve to disengage from the upper recess, a pullingof the trigger counterclockwise rotates both the pivotal member and thelower hook to unlock the front sliding sleeve, the auxiliary biasingmember expands to push the rear sliding sleeve forward, the upper hookis pressed by the roller in the forward movement of the rear slidingsleeve to disengage from the upper recess, the pivotal member pivotablypushes the lower hook to disengage from the lower recess, the auxiliarybiasing member expands to push the rear sliding sleeve rearward, themain tube moves rearward to compress the cup member until the flangecontacts the limit member and the rear inlet communicates with the airchamber, second pressurized gas flows through the barrel via the airchamber, the rear inlet, the main tube, and the gas piston to dischargeone of the at least one pellet out of the barrel, a portion of thesecond pressurized gas flows into the diversion channel to push thefront sliding sleeve rearward by compressing the auxiliary biasingmember and expanding the main biasing member, the gas piston movesrearward to allow a next one of the at least one pellet to enter thereceptacle, a stop of flowing the second pressurized gas pushes the cupmember forward to disengage the rear inlet from the air chamber, theupper hook lockingly engages the upper recess, the lower hook lockinglyengages the lower recess, the main biasing member, the main biasingmember expands, the auxiliary biasing member compresses, and both thefront and rear sliding sleeves move forward to dispose the trigger inthe ready position.